Rust can compile to WASM, so let's use it for front-end code as well.
To compile the front-end:
```
cargo install cargo-web
cargo web deploy -p plume-front
```
All the template are now compiled at compile-time with the `ructe` crate.
I preferred to use it instead of askama because it allows more complex Rust expressions, where askama only supports a small subset of expressions and doesn't allow them everywhere (for instance, `{{ macro!() | filter }}` would result in a parsing error).
The diff is quite huge, but there is normally no changes in functionality.
Fixes#161 and unblocks #110 and #273
* Add search engine to the model
Add a Tantivy based search engine to the model
Implement most required functions for it
* Implement indexing and plm subcommands
Implement indexation on insert, update and delete
Modify func args to get the indexer where required
Add subcommand to initialize, refill and unlock search db
* Move to a new threadpool engine allowing scheduling
* Autocommit search index every half an hour
* Implement front part of search
Add default fields for search
Add new routes and templates for search and result
Implement FromFormValue for Page to reuse it on search result pagination
Add optional query parameters to paginate template's macro
Update to newer rocket_csrf, don't get csrf token on GET forms
* Handle process termination to release lock
Handle process termination
Add tests to search
* Add proper support for advanced search
Add an advanced search form to /search, in template and route
Modify Tantivy schema, add new tokenizer for some properties
Create new String query parser
Create Tantivy query AST from our own
* Split search.rs, add comment and tests
Split search.rs into multiple submodules
Add comments and tests for Query
Make user@domain be treated as one could assume
we move our PostgreSQL specific migrations to a subdirectory.
The SQLite migrations have been created by running `diesel` against a
copy, and then fixing what's broken.
In the end i reduced all modifications to a single create, since we
*are* starting out fresh with SQLite.
n.b.: i'm not entirely happy with the results yet, because diesel
heavily modifies our `plume-models/src/schema.rs`.
I'll keep fiddling until we have the same types between the two
databases.
