Use context term boosts for Rocket.Chat Search with Chatpal provider

[westei]

With chatpal/chatpal-search-solr-ext#7 it is now possible to parse raw solr queries to chatpal. This allows to use the boosts provided by the Rocket.Chat query providers for context query.

The Rocket.Chat search query needs to use the same text parameter as present so that context queries do work with Rocket.Chat is configured with an other query provider as Chatpal.

But within the params the new query parameter can be used to provide a more precise context query that is only interpreted if Chatpal is configured as Rocket.Chat search provider

this Query needs to look like {term1}^{boost1} {term2}^{boost2} "{multi word term3}"^{boost3}

[westei]

Notes:

• Changed Milestone to 0.9.0 as we will not do a 0.8.1 release
• this requires https://github.com/assistify/Rocket.Chat/pull/601 to work