merge projects file-utils, byte-utils and pdb-utils

It turned out that most projects needed at least
two of the utils projects. file-utils and byte-utils
had only one class. Merging them made sense.

pdb-ui/build.gradle

@@ -14,7 +14,6 @@ dependencies {
 	implementation project(':pdb-plotting')
   implementation project(':pdb-js')
   implementation project(':pdb-utils')
-  implementation project(':file-utils')
   
   implementation lib_commons_lang3
   implementation lib_primitive_collections
@@ -27,7 +26,6 @@ dependencies {
 	testImplementation(lib_spring_boot_test){
 		exclude module: 'spring-boot-starter-logging'
 	}
-	testImplementation project(':file-utils')
 }
 
 jar {