Bump version to 1.5.0

Since 1.4.0 was set, get_corpus_size() and get_word_frequency() were added, the
two leaks in the collocator lookup are fixed and the build no longer requires a
rocksdb 5.11 built from source, but does require C++17. That is more than a
patch release, so the minor version goes up.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Change-Id: Ib410c11f8b773d4153c6be4e83bb3367fcf4193b
diff --git a/CMakeLists.txt b/CMakeLists.txt
index f67f953..6fccb26 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -1,5 +1,5 @@
 cmake_minimum_required(VERSION 3.9)
-project(collocatordb VERSION 1.4.0 DESCRIPTION "Storing and retrieving collocation counts based on RocksDB")
+project(collocatordb VERSION 1.5.0 DESCRIPTION "Storing and retrieving collocation counts based on RocksDB")
 set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -g -fno-rtti")
 set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -g")