Import go to definition issues introduced with remappings #295 also discussion at #277

Removes "imp" snippet as it confuses the "import " + Ctrl Space to autocomplete all the defintions.

Author: juanfranblanco

Diff for: snippets/solidity.json

@@ -18,8 +18,9 @@
 			"body": "pragma abicoder v2;"
 		},
 		"import contract": {
-			"prefix": "imp",
-			"body": "import '${1:contract}';"
+			"prefix": "import",
+			"body": "import ",
+			"description": "Press Ctrl+Space to autocomplete imports"
 		},
         "contract declaration": {
 			"prefix": "con",

Diff for: src/server/definitionProvider.ts

@@ -635,9 +635,9 @@ export class SolidityDefinitionProvider {
   private resolveImportPath(importPath: string, contract: Contract): string {
     if (contract.isImportLocal(importPath)) {
       return contract.formatContractPath(path.resolve(path.dirname(contract.absolutePath), importPath));
-    } else if (this.project !== undefined) {
+    } else if (this.project !== undefined && this.project !== null) {
       const remapping = this.project.findImportRemapping(importPath);
-        if(remapping !== undefined) {
+        if(remapping !== undefined && remapping != null) {
             return contract.formatContractPath(remapping.resolveImport(importPath));
         } else {
             const depPack = this.project.findDependencyPackage(importPath);